1. Field of the Invention
This invention relates generally to wireless, computer controlled transaction processing within merchandising operations, and, more particularly, it relates to a communication network wherein much of such transaction processing is distributed between a centralized station and a plurality of portable data terminals
2. Description of the Related Art
Computer terminals and peripherals have become dramatically smaller and more portable. Many types of peripheral devices exist such as printers, modems, graphics scanners, text scanners, code readers, magnetic card readers, external monitors, voice command interfaces, external storage devices, and so on. Despite the reductions in size, computer terminals still must physically interface with the peripheral devices. This typically involves either the running of a cable from one of the computer terminal to each device (hereinafter xe2x80x9chard-wiringxe2x80x9d) or the computer terminal must be docked with the device while the information transfer is to take place.
Hard-wiring poses several problems. If there are many peripheral devices, there must be as many cables attached to the computer terminal. This place a strain on the input/output capabilities of many computer devices. In addition, the wired mass of cabling often creates an eyesore and safety hazard. In addition, attempts to hide cabling behind walls often proves very costly, and such hidden wires are always more difficult to relocate.
Another problem exists when several computer terminals share a peripheral device. Not only must each computer be connected, often via hard-wiring, to the peripheral device, but it must utilize a communication protocol for sharing the communication channel to the peripheral device with the other connected computer terminals. This poses significant problems with different types of computers that do not share a common hard-wired interface or communication protocol.
In smaller computer terminal settings, hand-held or portable terminals, the cabling and connection problem become more severe. For example, excess cabling can transform an otherwise light, portable device into either a stationary device or a heavy, luggable device having dangerous trip cords for cabling.
Physical connections created by hard-wiring often proves to be relatively expensive because cables break and must be replaced. Cable replacement is even more common in portable environments where cables are subject to frequent handling, temperature extremes, dropping and other physical trauma.
An operator who is using, holding or carrying several devices and feels all tied up is not just inconvenienced, he may be severely limited in his mobility and flexibility as he moves about the work area. This loss of mobility and flexibility directly undercuts the entire reason for having small and portable computers and peripheral devices, and greatly increases the likelihood of operator injury.
Attempts to alleviate or eliminate these problems have been made but have not been greatly successful. One solution is to incorporate a computer terminal and all of the peripherals into one unit. However, this solution proves unsatisfactory for several reasons. For example, the incorporation of many devices into one unit greatly increases the size and weight, thus jeopardizing the portability of the unit. Furthermore, incorporating all of the functions into one unit greatly reduces and, in most cases eliminates, the flexibility of the overall system. A user may only wish to use a hand-held computer terminal at times, but at other times may also need to use a printer or occasionally a code reader. An all-incorporated unit thus becomes either overly large because it must include everything, or very limiting because it does not include everything.
Another solution has been to set up Local Area Networks (LAN""s) utilizing various forms of RF (Radio Frequency) communication. The LAN""s to date, however, have been designed for large scale wireless communications between several portable computer terminals and a host computer. Therein, the host computer, itself generally a stationary device, manages a series of stationary peripherals that, upon requests to the host, may be utilized by the portable terminals.
Other large scale wireless communications have also been developed which use RF communication between several computer terminals and peripheral devices, but all proving to be ineffective as a solution. For example, these systems require the peripheral devices to remain active at all times to listen for an occasional communication. Although this requirement may be acceptable for stationary peripheral devices receiving virtually unlimited power (i.e., when plugged into an AC outlet), it proves detrimental to portable peripherals by unnecessarily draining battery power. Similarly, in such systems, the computer terminals are also required to remain active to receive an occasional communication not only from the other terminals or the host but also from the peripherals. Again, often unnecessarily, battery power is wasted.
Moreover, in merchandising operations, conventional, stationary merchandizing terminals (e.g., electronic cash registers) which are typically hard-wired to a power source, local communication network, and/or telephone lines provide customer checkout service at a fixed location. Once such terminals are installed, they cannot be easily moved without significant effort in not only moving the terminals themselves but also in the relocation of the power source (typically an AC outlet), communication network and telephone line connections.
Also in merchandising operations, a common problem is found in handling light and heavy checkout loading. To manage heavy customer checkout traffic, each merchandiser, guessing what the peak checkout traffic will be, installs a plurality of stationary merchandizing terminals within a store""s premises. If the guess proves too low, additional stationary terminals (each requiring power source, network and telephone connection, i.e., cabling installations) must be added, often causing floor layout problems and very expensive cabling installations which require the store to be temporarily closed. Alternately, if the guess proves too high, a merchandiser must either rip out the station and repair the facilities or suffer the costs of lost space and station upkeep. Furthermore, increases or decreases in customer traffic over time may covert a guess for good to bad, resulting in the need to modify a store""s terminal installations.
In addition, in periods of light checkout traffic (i.e., very few customers checking out in relation to the number of stationary merchandising terminals), most of the stationary merchandising terminals will not be used. In such situations, the space taken up by the stationary terminals is not justified. In periods of heavy checkout traffic (i.e., where numbers of customers wait in lines for access to each available stationary merchandising terminal), merchandisers fear that their customers will see the lines and forego their purchases, or, worse, will become so dissatisfied with the checkout wait that they will vow never to return.
Thus, it may be appreciated that it is often very difficult to predict the number of stationary merchandizing terminal installations that are or will be needed. Moreover, it is even more difficult and costly to change a store""s stationary merchandizing terminal installations to conform to such needs.
Attempts have been made to minimize the cost of removing or adding merchandizing terminal installations by replacing the network cabling with an RF communication channel. In such installations, each terminal is fitted with an RF transceiver for communicating, for example, with a centralized host computer located some distance away. However, even with such changes, the aforementioned problems have not been solved. For example, the merchandising terminals still require hard-wiring to a power source, telephone lines (if used) and peripherals. In addition, the RF transmissions used to communicate with the centralized host need relatively high transmission power, requiring access to a virtually unlimited power source (such as is available through an AC outlet).
Thus, there is a need for a communication network that supports the changing need for merchandising terminals and their peripherals without requiring conventional removal, installation or relocation costs.
The present invention solves the foregoing problems in a longer range communication network having a mobile service station comprising a plurality of network devices. One of the plurality of network devices is an access point device which is capable of communicating on the longer range communication network. The plurality of network devices together form a shorter range communication network operating as a subnetwork in the longer range communication network. The access point device may enter a low power consumption state when it is not communicating on either the longer range communication network or the shorter range communication network.
In another embodiment, the access point device participates as a slave device to the longer range communication network pursuant to a first communication protocol, and participates as a master device to the shorter range communication network pursuant to a second communication protocol. The access point device may resolve conflicts between the first and second communication protocols.
In a further embodiment, a communication system comprises a wireless premises network and a wireless peripheral subnetwork having a relatively shorter range than the wireless premises network. The system further. has a mobile network device capable of communicating with both the wireless premises network and the wireless peripheral subnetwork, as well as a mobile service station. The mobile service station has a battery power supply, and is configured to mount the mobile network device. The mobile network device may participate on the peripheral subnetwork when mounted on the mobile service station.
When within the relatively shorter range of the peripheral subnetwork, the mobile network device participates on the peripheral subnetwork. When within range of the wireless premises network, the mobile network device may participate on the wireless premises network. Furthermore, the mobile service station may mount a peripheral device which participates on the peripheral subnetwork.
The mobile network device may participate as a slave device to the wireless premises network pursuant to a first communication protocol while participating as a master device to the peripheral subnetwork pursuant to a second communication protocol. The mobile network device resolves conflicts between the first and second communication protocols. When not communicating with either the wireless premises network or the peripheral subnetwork, the mobile network device may enter a state of low power consumption.
In a still further embodiment, the wireless premises network has a first plurality of network devices, and the peripheral subnetwork also has a second plurality of network devices. When within range of one of the second plurality of network devices, the mobile network device participates as a master device in the peripheral subnetwork, and when within range of one of the first plurality of network devices, the mobile network device participates as a slave device in the wireless premises network.
In yet another embodiment, the system has a network device independent of the mobile network device. The network device has means for identifying a range value which indicates the distance between the network device and the mobile network device. The network device responds to the identifying means by transmitting the range value to the mobile network device, and, when the mobile network device receives the range value, the mobile network device identifies an appropriate data rate for subsequent transmission to the network device. Alternatively, the network device may respond to the identifying means by instead indicating to the mobile network device an appropriate rate for subsequent data transmission to the network device. In addition, the mobile network device may have means for identifying battery parameter information which may be used along with the range value received from the network device to identify an appropriate power level and data rate for subsequent transmission to the network device.
In another embodiment, the communication system is used to facilitate a transaction. The communication system comprises a mobile service station operating on a first communication network. The mobile service station has a network device for capturing transaction information, and for generating therefrom code information representative of the transaction information. The mobile service station further comprises a code printer for printing the code information in code form. The system also has a host service station operating on a second communication network. The host service station comprises a second network device for reading the code and for generating therefrom the code information. The second network device converts the code information into the transaction information which the code information represents.